Research on failure behavior of 18CrNiMo7-6 steel

• Published in: Engineering failure analysis Vol. 150; p. 107306
• Main Authors: Wei, Zhan-cheng, Yan, Zhi-feng, Zhang, Jin-wen, Zhang, Hong-xia, Wang, Zhi-xiang, Wang, Wen-xian
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2023
• Subjects: 18CrNiMo7-6 steel; Damage accumulation; Fatigue performance; Microstructure evolution; Tensile properties; Damage accumulation; Tensile properties; 18CrNiMo7-6 steel; Microstructure evolution; Fatigue performance
• ISSN: 1350-6307; 1873-1961
• DOI: 10.1016/j.engfailanal.2023.107306

•The deformation failure behavior of 18CrNiMo7-6 steel was studied under different loads.•The microstructure evolution of 18CrNiMo7-6 steel was analyzed under different loads.•The damage accumulation was calculated by the deformation work.•The identical damage failure mechanism was discovered under different loads. In this paper, the deformation damage and failure behavior of 18CrNiMo7-6 steel under dynamic-static loading was investigated. The results revealed that the material fracture mode under static tensile loading had obvious plastic fracture characteristics, which different from that under dynamic cyclic loading. Moreover, the degree of microstructure evolution under static tensile loading was higher than those under dynamic cyclic loadings. However, the damage inside the material is gradually accumulated under dynamic-static loading. The number of dislocations and low-angle grain boundaries in the internal microstructure increased, while the grain orientation tended to be hard orientation, and the deformation curves under different loadings exhibited variations of properties. The theoretical model of damage deformation was proposed to illustrate the damage failure process inside the material.